Tank ball



Dec. 13, 1927.

A. H. CANFIELD TANK BALL Original Filed Nov. 2. 1922 Patented Dec. 13, 1927.

, UNITED STATES PATENT OFFICE.

-ALBER'I1 H. GANFIELD, F BRIDGEPORT,CbNNlliCTICU'IL TANK BALL.

Original application filedNovember 2, 1922, Serial No. 398,593. Divided and this application filed V March 24, 1925.

This invention pertains to an improved tank ball and has for its main object the production of a superior ball without seams or joints.

The apparatus whereby the method of producing the ball is carried out is set forth in my co-pending application Ser. No.

598,593, filed on or about November 2, 1922,

wherein the method is claimed, which application eventuated in Patent Number 1,535,715, dated April 28, 1925. The present application is a division of that application and is presented as such pursuant to the requirements of the Patent Office.

Two forms of the ball falling within the scope of my invention are illustrated in the annexed drawings, wherein,-

Fig. 1 is a sectional elevation of a completed ball; and

Fig. 2 is a similar view showing a slight modification of the structure.

The ball is preferably produced in the manner set forth in the application above referred to, which method may be stated in general terms as follows.

There is placed within a cavity formed in a mold section material sufficient to produce the body of the ball in its entirety, and there is then forced onto said material a second 30 mold section. This section section has a core mounted in a cavity formed therein and in spaced relation to the walls of the cavity, said core likewise having an out wardly extending portion. When the mold sections are brought together, the outwardly extending portion contacts the material and causes a flow thereof throughout the cavities in the mold. is finally vulcanized.

More specifically stated, the method con sists in placing a disk or sheet of hard curing rubber within the cavity formed in the mold, and placing upon such disk a body of soft curing rubber in a quantity suflicient to be co-extensive of the upper and lower portions of the ball. The operations as recited above are carried out to produce the finished product.

There is thus produced a tank ball having a relatively stiff upper portion and a softer seating portion. The body of the ball presents .no seams or joints, as where the sections of the ball are pre-formed and joined to ether by a vulca-nizing operation.

11 the drawings, and referring first to The ball thus produced Serial No. 18,013.

in the act of molding the structure. The rib stifi'ens the ball against collapse.

The upper outer portion of the ball is formed of hard curing stockwhich becomes, 1n a fact, an integral portion of the inner portion of the upper part of the ball which is formed, asabove noted, of soft curing stock, which'stock continues into the lower valve-seating portion 24 of the ball. The outer, relatively hard portion of the upper part of the ball prevents the ball from collapsing, and together with the thickened 'inner portion formed of softer material, en-

sures suflicient rigidity in the structure to enable it to function under all working conditions.

The ball is produced in a single heat and there is no pre-forming or pre-molding of separate sections or halves requiring subsequent joining with a consequent seam. The outer upper end facing formed'of the harder material becomes amalgamated with the underlying material. lnpractice, unless different colored stock is employed, the line of juncture between the two grades of material is imperceptible. I

The usual spud 19 is positioned in the upper end of the ball.

In Fig. 2 a slightly modified formation of the tank bulb is illustrated, wherein a layer of fabric, denoted by 29, is shown as lying between and embedded in the adjacent faces or portions of the inner, relatively soft rubber and the harder outer facing structure during the process of manufacturmg by imposing a piece of frlctioned fabric .upon the disk of which the outer hard facbody. Y This may be readily embodied in the body as a whole is produced, is placed in the mold. The presence of this fabric may be found advantageous in tank balls of the larger sizes.

What is claimed is:

1. As a new article of manufacture, a tank ball comprising a body portion formed of relatively soft rubber coextensive of the ball and Without seam or joint, the upperportion of the ball having formed therewith an portion of the ball having formed thereouter layer of relatively hard rubber, said with alay-er of relatively hard rubber, said 10 upper portion likewise having 21/ strengthenupper portion likewise having a strengthing fabric embodied therein. ening fabric embodied therein.

5 2. As a neW article of manufacture, a In testimony whereof I have signed my tank ball comprising a body portion formed name to this specification. of relatively soft rubber coextensive of the ball and without seam or joint, the upper V ALBERT H. CANFIELD. 

